This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-018704, filed Jan. 27, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to a system for optically performing position detection and data communication.
In recent years, systems for performing position detection and data communication for an object are used in various scenes. Examples of such systems are a PHS (Personal Handyphone System) used for voice communication position search and voice communication, a VICS (Vehicle Information Communication System)-compatible car navigation system for detecting a vehicle position and receiving traffic information, and a mobile robot communication system used for position detection (PD) and data communication (DC) for a partner robot. Table 1 shows conventional system examples of this type.
These conventional systems use xe2x80x9cradio wavesxe2x80x9d for position detection and data communication. Use of the systems is inhibited in hospitals which restrict the use of radio waves. Use of the system is also limited in the outerspace where they are exposed to strong electromagnetic waves.
A technique exclusively used for only position detection without using any radio wave has been developed. More specifically, a plurality of light sources are attached to a target position detection object, and the object is sensed with an image sensor. On the basis of the light point, coordinates of the sensed image, the position or motion of the object is detected using triangulation.
This technique is widely used in the field of image measurement including motion capture. However, this technique is inherently different from the above-described PHS and VICS-compatible car navigation and therefore cannot be directly applied to a system used for position detection and data communication for an object. Additionally, in the conventional image measurement technique, the position detection accuracy is insufficient, and the position of an object that is simultaneously translating and rotating is hard to accurately detect.
Hence, demand has arisen for a technique of simultaneously performing position detection and data communication regardless of presence/absence of limitations on radio waves and sufficiently increasing the position detection accuracy.
The present invention has been made in consideration of the above situation, and has as its object to provide a system capable of simultaneously realizing position detection and data communication independently of radio wave conditions.
The gist of the present invention is to simultaneously optically perform position detection and data communication. FIG. 18 shows the principle of a technique of simultaneously performing position detection and data communication using light. A light-emitting element for position indication and data transmission is provided in a transmitting apparatus, and an image sensing element for sensing the light emission state of the light-emitting element is provided in a receiving apparatus. The position is detected, using triangulation, from the image of the light-emitting element sensed by the image sensing element, and data communication is done by blinking the light-emitting element. A system for performing both position detection and data communication using light in this way can be used even in a hospital where the use of radio waves is restricted or outerspace where the system is exposed to strong electromagnetic waves.
According to the first aspect of the present invention, there is provided a transmitting apparatus comprising:
a support member;
a position indicating section having a plurality of first light-emitting elements supported by the support member, the first light-emitting elements being turned on to indicate a position of the transmitting apparatus; and
a data transmitting section having a second light-emitting element supported by the support member, the second light-emitting element blinking in correspondence with data to transmit the data.
The transmitting apparatus may further comprise a data processing section for supplying different kinds of information to the data transmitting section as the data, and a sensor for acquiring information associated with a target measurement object and supplying the information to the data processing section as the data.
According to the second aspect of the present invention, there is provided a receiving apparatus for detecting the position of the transmitting apparatus of the first aspect and receiving the data transmitted from the transmitting apparatus, comprising:
an image sensing element for sensing the first and second light-emitting elements;
an image processing section for separately extracting image components of the first and second light-emitting elements from a sensed image obtained by the image sensing element;
a position detecting section for detecting the position of the transmitting apparatus on the basis of the image components of the first light-emitting elements extracted by the image processing section; and
a data detecting section for detecting the data on the basis of the image component of the second light-emitting element extracted by the image processing section.
The receiving apparatus may further comprise an A/D (analog/digital) converter for A/D-converting the sensed image obtained by the image sensing element to form a digital image.
According to the third aspect of the present invention, there is provided a system for performing position detection and data communication, comprising the transmitting apparatus of the first aspect and the receiving apparatus of the second aspect.
This system can be used as a hospital monitoring system, a docking assist system for docking a moving body to a stationary body, or a docking assist system for docking first and second moving bodies to each other.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.